Hello. My name is David Brin. I am an astronomer who is better known as an author of books such as The Postman (filmed by Kevin Costner in 1998) and The Transparent Society.

I am also a member of the Transmissions from Earth subcommittee of the International Academy of Astronautics SETI Permanent Study Group (http://iaaseti.org), the advisory body that has been charged with working out protocols and conventions having to do with the Search for Extraterrestrial Intelligence, or SETI. This study group has drafted and circulated the main internationally accepted documents concerning recommended standards for researchers and others who might receive or initiate contact by radio or other means with extrasolar civilizations.

I am writing to inform you that this subcommittee exists. A Protocol exists. And since you have announced an intention to beam messages from Earth into interstellar space, you may wish to familiarize yourself with these matters. What you propose to do comes under the category of "active SETI" and it has implications of which you may not be aware.

While this is not an official or majority point of view, a number of members of the subcommittee have called for a moratorium when it comes to deliberate beaming of messages from Earth at detection levels significantly above background. The matter - controversial both inside the committee and outside - is still being debated. In any event, enough prestigious scholars and scientists have expressed concern that it might seem reasonable to ask that you pause a little and consider.

At present there is a limited range of ways that Earth civilization has become detectable. A common belief holds that TV broadcasts have already screeched loudly enough for all to hear, but this fable has been disproved. Beyond a few light years, these signals - and even military radar beams - fade into background.

It is narrowly targeted beams that will far more likely call attention to our planet. Should we transmit such beams while knowing absolutely nothing about the situation out there?

Everybody has a favorite opinion about what interstellar civilizations will be like. Hollywood portrays bizarre threats. Many others feel that advanced societies will naturally be benign. These unproved opinions are not at issue.

What is at issue is the presumption that a few people may commit our world down a no-return road, without taking any time to discuss the matter with others who have pondered deeply on this subject, and who might shed light on the possibilities, both good and bad.

While smiling at the ingenuity and entertainment value of this public relations gambit, I am also hoping that you will consider dipping a little deeper into the subject. There may be ways to get the effect you desire, while still behaving as responsible citizens of a tiny planet, all alone in a dark and unknown wilderness.

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